1. Field of the Invention
The present invention generally relates to a display system. More particular, the present invention relates to a display controller provided with dynamic output clock.
2. Description of Related Arts
Display systems are employed to process source image data into output image data for displaying on a display screen thereof. The source image data is usually provided by a graphics controller such as a graphics card, video decoder, digital camera, etc. and the resolution of the source image data is normally predetermined. Therefore, the source image data has to be resized or scaled to the appropriate resolution such that the display screen can correctly display the output image data. Accordingly, a device used to process the source image data into the associated output image data is so-called a “display controller.”
The display controller usually utilizes a line buffer for read/write operations, which normally subjects to underrun or overrun due to read/write racing. Although firmware adjustment approach has been conventionally utilized to solve the underrun or overrun issues, the user is required to realize the detailed operations of the display controller and manually adjust the associated parameters via the firmware intervention.
Thus, there is a need for a simple hardware-implemented display controller for automatically scaling an image that gives good image output quality, fast tuning result, and a user-friendly interface.